diff --git a/tools/compliance/readgraph_test.go b/tools/compliance/readgraph_test.go
new file mode 100644
index 0000000..6248209
--- /dev/null
+++ b/tools/compliance/readgraph_test.go
@@ -0,0 +1,139 @@
+// Copyright 2021 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package compliance
+
+import (
+	"bytes"
+	"sort"
+	"strings"
+	"testing"
+)
+
+func TestReadLicenseGraph(t *testing.T) {
+	tests := []struct {
+		name            string
+		fs              *testFS
+		roots           []string
+		expectedError   string
+		expectedEdges   []edge
+		expectedTargets []string
+	}{
+		{
+			name: "trivial",
+			fs: &testFS{
+				"app.meta_lic": []byte("package_name: \"Android\"\n"),
+			},
+			roots:           []string{"app.meta_lic"},
+			expectedEdges:   []edge{},
+			expectedTargets: []string{"app.meta_lic"},
+		},
+		{
+			name: "unterminated",
+			fs: &testFS{
+				"app.meta_lic": []byte("package_name: \"Android\n"),
+			},
+			roots:         []string{"app.meta_lic"},
+			expectedError: `invalid character '\n' in string`,
+		},
+		{
+			name: "danglingref",
+			fs: &testFS{
+				"app.meta_lic": []byte(AOSP + "deps: {\n  file: \"lib.meta_lic\"\n}\n"),
+			},
+			roots:         []string{"app.meta_lic"},
+			expectedError: `unknown file "lib.meta_lic"`,
+		},
+		{
+			name: "singleedge",
+			fs: &testFS{
+				"app.meta_lic": []byte(AOSP + "deps: {\n  file: \"lib.meta_lic\"\n}\n"),
+				"lib.meta_lic": []byte(AOSP),
+			},
+			roots:           []string{"app.meta_lic"},
+			expectedEdges:   []edge{{"app.meta_lic", "lib.meta_lic"}},
+			expectedTargets: []string{"app.meta_lic", "lib.meta_lic"},
+		},
+		{
+			name: "fullgraph",
+			fs: &testFS{
+				"apex.meta_lic": []byte(AOSP + "deps: {\n  file: \"app.meta_lic\"\n}\ndeps: {\n  file: \"bin.meta_lic\"\n}\n"),
+				"app.meta_lic":  []byte(AOSP),
+				"bin.meta_lic":  []byte(AOSP + "deps: {\n  file: \"lib.meta_lic\"\n}\n"),
+				"lib.meta_lic":  []byte(AOSP),
+			},
+			roots: []string{"apex.meta_lic"},
+			expectedEdges: []edge{
+				{"apex.meta_lic", "app.meta_lic"},
+				{"apex.meta_lic", "bin.meta_lic"},
+				{"bin.meta_lic", "lib.meta_lic"},
+			},
+			expectedTargets: []string{"apex.meta_lic", "app.meta_lic", "bin.meta_lic", "lib.meta_lic"},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			stderr := &bytes.Buffer{}
+			lg, err := ReadLicenseGraph(tt.fs, stderr, tt.roots)
+			if err != nil {
+				if len(tt.expectedError) == 0 {
+					t.Errorf("unexpected error: got %w, want no error", err)
+				} else if !strings.Contains(err.Error(), tt.expectedError) {
+					t.Errorf("unexpected error: got %w, want %q", err, tt.expectedError)
+				}
+				return
+			}
+			if 0 < len(tt.expectedError) {
+				t.Errorf("unexpected success: got no error, want %q err", tt.expectedError)
+				return
+			}
+			if lg == nil {
+				t.Errorf("missing license graph: got nil, want license graph")
+				return
+			}
+			actualEdges := make([]edge, 0)
+			for _, e := range lg.Edges() {
+				actualEdges = append(actualEdges, edge{e.Target().Name(), e.Dependency().Name()})
+			}
+			sort.Sort(byEdge(tt.expectedEdges))
+			sort.Sort(byEdge(actualEdges))
+			if len(tt.expectedEdges) != len(actualEdges) {
+				t.Errorf("unexpected number of edges: got %v with %d elements, want %v with %d elements",
+					actualEdges, len(actualEdges), tt.expectedEdges, len(tt.expectedEdges))
+			} else {
+				for i := 0; i < len(actualEdges); i++ {
+					if tt.expectedEdges[i] != actualEdges[i] {
+						t.Errorf("unexpected edge at element %d: got %s, want %s", i, actualEdges[i], tt.expectedEdges[i])
+					}
+				}
+			}
+			actualTargets := make([]string, 0)
+			for _, t := range lg.Targets() {
+				actualTargets = append(actualTargets, t.Name())
+			}
+			sort.Strings(tt.expectedTargets)
+			sort.Strings(actualTargets)
+			if len(tt.expectedTargets) != len(actualTargets) {
+				t.Errorf("unexpected number of targets: got %v with %d elements, want %v with %d elements",
+					actualTargets, len(actualTargets), tt.expectedTargets, len(tt.expectedTargets))
+			} else {
+				for i := 0; i < len(actualTargets); i++ {
+					if tt.expectedTargets[i] != actualTargets[i] {
+						t.Errorf("unexpected target at element %d: got %s, want %s", i, actualTargets[i], tt.expectedTargets[i])
+					}
+				}
+			}
+		})
+	}
+}